I prefer black lights :)

-----Original Message-----
From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Ron
Casciato via CnC-List
Sent: Friday, September 19, 2014 11:41 AM
To: 'Joe Della Barba'; cnc-list@cnc-list.com
Subject: Re: Stus-List Red light myth?

Ted:

Thanks for the description of what's happening to my eyes........makes lotd
of things "clearer".

Incidentally, my wife's new Mercedes has "ambient lighting" surrounding the
interior at night which is Amber, I'm told that I can change it to red or
blue, but I agree that the amber is a very nice surrounding for night
driving.

The ambient lighting comes from strips of LEDs??? Along each side of the
door trim moldings under the window sill both front and back.

Best,

Ron C.


-----Original Message-----
From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Joe Della
Barba via CnC-List
Sent: Friday, September 19, 2014 10:07 AM
To: cnc-list@cnc-list.com
Subject: Re: Stus-List Red light myth?

Red light for night vision is NOT a myth, but there are some issues with it.
I have long experience with it both sailing and as a pilot.
Any decent camera has a lens made of different types of glass layered
together or otherwise designed to focus red, green, and blue light in the
same spot. Our eyes do not - we have a simple one-element lens optimized
around green light. Red light is very poor for doing fine detail work or
reading small print. Most people lose flexibility in their lens as they age
and usually this results in not being able to focus as close as before -
i.e. reading glasses. This also affects the ability to focus red light. I
used to teach in a plane that only had red panel lighting and some of my
older students had a very hard time reading the instruments while I -
younger back then - had no issue at all. Red light is also horrible for
reading charts, all the color detail washes out.  We had another plane with
white instrument lights and red area lights for the cockpit. I liked that
one the best, we would turn up the red light enough to see what was what and
turn down the instrument lights until they were a very dim yellowish white.
If the white is dim enough it didn't ruin our night vision and was much
easier to read than just using the red overhead lights. Mercedes and Porsche
use a similar idea, or at least they did back when I had them. Both cars
used black dial instruments with orange-red needles and white lights. You
could dim it way down and still read the gauges just fine. BMW uses an
orange-red that works pretty well and Audi uses pure red. Once you get past
a "certain age" the organge-ish (amber?) color is easier to focus and I
think what you lose moving away from pure red you gain by not needing it to
be so bright* to focus.
* more camera tech. Bright light, for both cameras and your eyes, means
reducing the amount of light with your iris getting smaller or the
mechanical version in a camera. Due to the physics involved you gain depth
of field by doing this, so things are in focus in front of and behind the
focus point. If you are far sighted, you might be able to read something a
lot closer in bright light than in dim light because of this and red light
makes this happen even more.
So - IMHO and I Am Not An Eye Doctor - I have set my boat up with all red
lights for night sailing. The red is fine for getting around and finding
large objects. My compass has big enough markings to look fine in red light
as do the engine gauges. I can deploy a small dim white light at the chart
table if I need to, but it is a rare occasion now for me to work on paper
charts. I do set the computer plotter to be as dim as it can be an turn down
the screen brightness on the laptop to the lowest setting, but still in
color. If I shift it to "night mode" with black background I seem lose a lot
of detail. I do see many plotters WAY too bright at night. I see boats going
by with the helmsman clearly illuminated by the plotter. I do not see how
they can see even as far as the bow.

Joe Della Barba
Coquina
C&C 35 MK I


_______________________________________________
This List is provided by the C&C Photo Album

Email address:
CnC-List@cnc-list.com
To change your list preferences, including unsubscribing -- go bottom of
page at:
http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com


_______________________________________________
This List is provided by the C&C Photo Album

Email address:
CnC-List@cnc-list.com
To change your list preferences, including unsubscribing -- go bottom of
page at:
http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com



_______________________________________________
This List is provided by the C&C Photo Album

Email address:
CnC-List@cnc-list.com
To change your list preferences, including unsubscribing -- go bottom of page 
at:
http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com

Reply via email to